Normal HeLa Cells Research Articles

Phyto-mediated synthesis of Ag, ZnO, and Ag/ZnO nanoparticles from leave extract of Solanum macrocarpon: Evaluation of their antioxidant and anticancer activities

Silver, zinc oxide, and silver/zinc oxide nanocomposites were prepared from the facile green process using Solanum macrocarpon leave extract. Ag and ZnO nanoparticles (NPs) were composited with the aim of enhancing the synergy for improved antioxidant and anticancer activities. In the synthesis process, the formation of Ag NPs was initially observed by a colour change and was confirmed by the appearance of surface plasmon resonance (SPR) bands. Based on the crystallographic analysis of the diffraction patterns, the phyto-capped silver NPs possessed a crystalline character, featuring a lattice structure of face-centered cubic (FCC) and an estimated crystallite size of around 7.2 nm. The formation of a hexagonal crystal structure of spherical morphology was confirmed for the ZnO, while the Ag/ZnO composite showed additional planes due to the silver nanoparticles in the cubic phase. The scavenging activities of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals and their anticancer potency on normal HEK and cancerous HELA cells were examined in comparison to standard drugs. They demonstrated remarkable IC50 values that were better than the control drugs. This study provides helpful insight into the synergy between Ag and ZnO nanoparticles for the possible development of new anticancer and antioxidant agents.

Bioimaging-guided discrimination of normal/cancer cells using Ag+-mediated red fluorescent carbon dots

Glutathione (GSH) serves as a significant cancer-related biomarker that plays a pivotal role in preserving intracellular homeostasis. However, the structural and functional similarities between GSH and other biothioles (cysteine and homocysteine), make it difficult to distinguish GSH from them. In this study, we have developed a novel fluorescent probe utilizing silver-mediated red emissive carbon dots (RCDs@Ag+) for the discrimination of cancer cells from normal cells through the bioimaging of glutathione (GSH). The fluorescence intensity of RCDs is quenched significantly upon the addition of Ag+ (50 µM) and is recovered 95 % with the identical concentration of added GSH, without such effect occurring in cysteine and homocysteine. The fluorescence lifetime of the RCDs was found to be approximately 7.022 ns and the quantum yield was determined to be approximately 9.24 %. Further, RCDs@Ag+ are suitable for selectively detecting intracellular GSH due to their excellent biocompatibility, and low toxicity in normal NIH3T3 and HeLa cells. Most significantly, RCDs@Ag+ may be used as an excellent approach to spot cancer cells overexpressing GSH.

Target recognition assisted-primer exchange reaction (Ta-PER) for sensitive analysis of p53 gene and its application in analyzing amatoxin-treated samples.

Sensitive and reliable detection of thep53 gene plays a significant role in precise cancer targeting and in fundamental research. However, thesensitivity of existing p53 gene detection approaches remains to be improved. Herein, we develop a target recognition assisted-primer exchange reaction (Ta-PER) for sensitive analysis of thep53 gene. Ta-PER was initiated by the recognition of a designed dumbbell structure probe by thep53 gene. In Ta-PER, theprimer exchange reaction (PER) was combined with molecular beacon-based chain recycling to construct the signal amplification process. Through integrating target recognition with PER-based signal amplification, Ta-PER was established and exhibited a high detection sensitivity, with alimit of detection as low as 56 fM. In addition, the approach was also used to detect thep53 gene in normal HeLa cells and amatoxin-treated HeLa cells. The high level of thep53 gene in amatoxin-treated HeLa cells, which was approximately 1.67 times higher than that in HeLa cell extract, indicated the apoptosis of cells and suggested the promising prospect of the approach.

Cell type-specific orientation and migration responses for a microgrooved surface with shallow grooves.

Directional cell migration due to mechanosensing for invivo microenvironment, such as microgrooved surfaces, is an essential process in tissue growth and repair in both normal and pathological states. Cell migration responses on the microgrooved surfaces might be reflected by the cell type difference, which is deeply involved in cellular physiological functions. Although the responses are implicated in focal adhesions (FAs) of cells, limited information is available about cell migration behavior on the microgrooved surfaces whose dimensions are comparable with the size of FAs. In the present study, we investigated the cell orientation and migration behavior of normal vascular smooth muscle cells (VSMCs) and cervical cancer HeLa cells on the microgrooved surface. The cells were cultured on the PDMS substrate comprising shallow grooves with 2-µm width and approximately 150-nm depth, which indicates the same order of magnitude as that of the horizontal and vertical size of FAs, respectively. The cell migration and intracellular structures were analyzed by live cell imaging and confocal fluorescence microscopy. The intracellular tension was also assessed using atomic force microscopy (AFM). VSMCs presenting well-aligned actin stress fibers with mature FAs revealed marked cell elongation and directional migration on the grooves; however, HeLa cells with nonoriented F-actin with smaller FAs did not. The internal force of the actin fibers was significantly higher in VSMCs than that in HeLa cells, and the increase or decrease in the cytoskeletal forces improved or diminished the sensing ability for shallow grooves, respectively. The results strongly indicated that directional cell migration should be modulated by cell type-specific cytoskeletal arrangements and intracellular traction forces. The differences in cell type-specific orientation and migration responses can be emphasized on the microgrooves as large as the horizontal and vertical size of FAs. The microgoove structure in the size range of the FA protein complex is a powerful tool to clarify subtle differences in the intracellular force-dependent substrate mechanosensing.

Visnagin inhibits cervical cancer cells proliferation through the induction of apoptosis and modulation of PI3K/AKT/mTOR and MAPK signaling pathway

Cervical cancer, a silent killer is a second most common type of malignant tumor detected in women’s world wide. In modern medicine the usage of phytochemicals to develop drugs for treating various chronic diseases is rapidly increasing. One such phytochemical is visnagin, a furanochrome present in fruits of Ammi visnaga . We investigated the anticarcinogenic potency of visnagin against human cervical carcinoma cells. The antioxidant potency of visnagin was analyzed with FRAP assay, DPPH assay, Chemiluminscence assay and ORAC assay. The cytotoxic effect of visnagin on normal epithelial Vero cells and human cervical cancer HeLa cells were analyzed using MTT assay. The effect of visnagin on antioxidant system was examined by measuring the levels of TBARS, SOD and GSH using the colorimetric assay techniques. DCFH-DA staining, AO/EtBr staining, propidium iodide staining was performed to assess the apoptotic induction potency of visnagin against cervical cancer cells. The ability of visnagin to inhibit cancer cell migration was examined with scratch wound assay. The anticarcinogenic property of visnagin was confirmed by analyzing the gene expression of PI3K/AKT/mTOR signaling proteins and MAPK signaling proteins using qPCR analysis. Visnagin exhibited increased Trolox equivalent value in all the four antioxidant potency estimating experiments. Visnagin induced cytotoxic effect only on carcinoma cells, decreased the antioxidants and increased the generation of ROS. It also induced apoptosis and inhibited the cancer cell migration. The qPCR analysis confirms visnagin decreases the gene expression cell cycle regulating protein of both PI3K/AKT/mTOR and MAPK pathway. Overall our results authentically prove visnagin inhibits the progression of cervical cancer in vitro. Therefore it can be an ideal drug of choice which can subject to further investigation for treating cervical cancer.

A Comparative Study of the Cytotoxic Effects and Oxidative Stress of Gossypol on Bovine Kidney and HeLa Cell Lines

Background: Cotton seed is one of the main sources of protein in animal feeds, containing gossypol, which has been shown to have toxic effects. Results reported by various studies also indicate the anti-cancer effects of gossypol on various cell types. However, its toxic effects on human and animal cells have not been fully established. This study was planned to investigate, for the first time, the cytotoxic effects and oxidative stress induced by gossypol on normal Bovine Kidney (BK) and HeLa cell lines, representing typical healthy and cancer cells, respectively. Methods: The BK and HeLa cell lines were treated for 24, 48 or 72 hours with 5, 10 or 20 ppm of gossypol (+/-). The cellular bio-availability and cytotoxicity were measured by MTT assay. The catalase and Malondialdehyde (MDA) levels were also measured to represent the oxidative stress parameters. Results: The percentages of cytotoxicity in BK and HeLa cell lines were calculated at a gossypol concentration of 5, 10 and 20 ppm over 24, 48 or 72 hours of incubation, respectively. The Lethal Concentration 50 (lC50) values were also determined for the two cell lines. No changes in the catalase and lipid peroxidase activities were observed in either cell line. Conclusion: The percentage of the gossypol cytotoxicity was concentration-dependent. By comparing the IC50 in both cell lines using one-way Analysis of Variance (ANOVA) analysis, a significant difference was observed, suggesting that Hela cells were less sensitive to gossypol than the BK cells. Lack of changes in the oxidative stress, as tested by catalase and MDA assays, demonstrated that gossypol did not induce oxidative stress in either cell line.

ASF1B promotes cervical cancer progression through stabilization of CDK9

Cervical cancer (CC) is one of the most deadly cancers in women, its current treatments still result in poor outcomes and developing the novel targets and therapeutic strategies are urgently needed. Recent studies have shown that anti-silencing function 1B (ASF1B) might be used as a new proliferation marker for cancer diagnosis and prognosis. However, the expression and function of ASF1B in cervical cancer remain unclear. Here, we induced ASF1B knockdown and overexpression in cervical cancer cell lines and detected the biological behavior changes in vitro. Furthermore, we established two murine models using stable ASF1B-shRNA HeLa cells or normal HeLa cells following AAV-shRNA-ASF1B administration to evaluate how suppression of ASF1B affects tumor growth. We showed that ASF1B functions as an oncogene in cervical cancer cells. Silence of ASF1B suppressed cervical cancer cell growth in vitro and in vivo, while, ASF1B overexpression accelerated cancer cell proliferation. Furthermore, ASF1B deficiency induced cell cycle arrest and apoptosis. Mechanistically, we found that ASF1B formed stable complexes with cyclin-dependent kinase 9 (CDK9), and positively regulated CDK9 stabilization. Taken together, tumorigenic ASF1B could be targeted to suppress cervical cancer tumor growth by inducing apoptotic cell death.

Macroscopic and microscopic analysis of the mechanical properties and adhesion force of cells using a single cell tensile test and atomic force microscopy: Remarkable differences in cell types

Many experimental techniques have been reported to provide knowledge of the mechanical behavior of cells from biomechanical viewpoints, however, it is unclear how the intercellular structural differences influence macroscopic and microscopic mechanical properties of cells. The aim of our study is to clarify the comprehensive mechanical properties and cell-substrate adhesion strength of cells, and the correlation with intracellular structure in different cell types. We developed an originally designed micro tensile tester, and performed a single cell tensile test to estimate whole cell tensile stiffness and adhesion strength of normal vascular smooth muscle cells (VSMCs) and cervical cancer HeLa cells: one half side of the specimen cell was lifted up by a glass microneedle, then stretched until the cell detached from the substrate, while force was simultaneously measured. The tensile stiffness and adhesion strength were 49 ± 10 nN/% and 870 ± 430 nN, respectively, in VSMCs (mean ± SD, n = 8), and 19 ± 17 nN/% and 320 ± 160 nN, respectively, in HeLa cells (n = 9). The difference was more definite in the surface elastic modulus map obtained by atomic force microscopy, indicating that the internal tension of the actin cytoskeleton was significantly higher in VSMCs than in HeLa cells. Structural analysis with confocal microscopy revealed that VSMCs had a significant alignment of F-actin cytoskeleton with mature focal adhesion, contrary to the randomly oriented F-actin with smaller focal adhesion of HeLa cells, indicating that structural arrangement of the actin cytoskeleton and their mechanical tension generated the differences in cell mechanical properties and adhesion forces. The finding strongly suggests that the mechanical and structural differences in each cell type are deeply involved with their physiological functions.

A nanohybrid composed of MoS2 quantum dots and MnO2 nanosheets with dual-emission and peroxidase mimicking properties for use in ratiometric fluorometric detection and cellular imaging of glutathione.

A nanohybrid probe was fabricated from manganese dioxide nanosheets (MnO2 NSs), molybdenum disulfide quantum dots (MoS2 QDs) and o-phenylenediamine (OPD) for ratiometric detection of glutathione (GSH) in aqueous solutions and living cells. The MoS2 QDs act as the fluorescent "turn off-on" units. The MnO2 NSs have 3 functions, viz. (a) as fluorescence quencher, (b) as fluorescence initiator for oxidized OPD (ox OPD) and (c) as selective recognizer of GSH. The quenched blue fluorescence of the MoS2 QDs can be restored by introducing GSH that reduces theMnO2 NSs. However, the green fluorescence of ox OPD is decreased through the loss of peroxidase activity of MnO2 NSs in the presence of GSH. Therefore, the ratio of the fluorescence intensities at 560 and 400nm (from ox OPD and MoS2 QDs, respectively) linearly decreases with increasing concentrations of GSH. Under the optimal conditions, the detection limit for GSH is as low as 90nM. The method was successfully applied to the determination of GSH in human serum samples. This nanohybrid also is shown to be membrane-permeable and to have low cytotoxicity. This paved the way to intracellular sensing of GSH in living normal HFF and cancerous HeLa cells. Additionally, by combining with logic gate, this assay was successfully applied to visually discriminate changes in the intracellular GSH. The combination of ratiometric fluorometry and peroxidase mimicking can provide a wide range of application in bioanalysis and intracellular imaging. Graphical abstract Schematic representation of the ratiometric fluorometric detection and cellular imaging of glutathione using a nanohybrid composed of MoS2 quantum dots and MnO2 nanosheets with dual (blue and greenemission and peroxidase mimicking properties.

Overexpression of the immediate early response 5 gene increases the radiosensitivity of HeLa cells.

The effects of the immediate early response 5 (IER5) gene on the sensitivity of HeLa cells to radiation remain unclear. In the present study, stably transfected HeLa cells resulting in the knockdown or overexpression of IER5 were investigated. In addition, xenografts of normal, IER5-silenced and -overexpressed HeLa cells were injected into nude mice and examined. The results demonstrated that the radiosensitivity of the IER5-overexpressed HeLa cells was significantly increased compared with that of the normal and IER5-silenced cells. The upregulation of IER5 effectively decreased cell proliferation and IER5 silencing promoted cell proliferation compared with that in the normal HeLa cells. Following irradiation of the cells with IER5 knockdown, cell cycle was arrested at the G2/M phase and an increase in the proportion of S phase cells was observed. By contrast, the overexpression of IER5 led to an increase in the proportion of G1 phase cells. Furthermore, the upregulation of IER5 inhibited tumor growth in vivo. The present findings demonstrate that the IER5 gene affects the radiosensitivity of HeLa cells and serves an important role in cell proliferation, suggesting that this gene may be a potential radiotherapeutic target in cervical cancer.

SNX11 Identified as an Essential Host Factor for SFTS Virus Infection by CRISPR Knockout Screening

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a highly pathogenic tick-borne bunyavirus that causes lethal infectious disease and severe fever with thrombocytopenia syndrome (SFTS) in humans. The molecular mechanisms and host cellular factors required for SFTSV infection remain uncharacterized. Using a genome-wide CRISPR-based screening strategy, we identified a host cellular protein, sorting nexin 11 (SNX11) which is involved in the intracellular endosomal trafficking pathway, as an essential cell factor for SFTSV infection. An SNX11-KO HeLa cell line was established, and SFTSV replication was significantly reduced. The glycoproteins of SFTSV were detected and remained in later endosomal compartments but were not detectable in the endoplasmic reticulum (ER) or Golgi apparatus. pH values in the endosomal compartments of the SNX11-KO cells increased compared with the pH of normal HeLa cells, and lysosomal-associated membrane protein 1 (LAMP1) expression was significantly elevated in the SNX11-KO cells. Overall, these results indicated that penetration of SFTSV from the endolysosomes into the cytoplasm of host cells was blocked in the cells lacking SNX11. Our study for the first time provides insight into the important role of the SNX11 as an essential host factor in the intracellular trafficking and penetrating process of SFTSV infection via potential regulation of viral protein sorting, membrane fusion, and other endocytic machinery.

Design, synthesis and biological evaluation of novel aryl-acrylic derivatives as novel indoleamine-2,3-dioxygenase 1 (IDO1) inhibitors.

Two series of novel aryl-acrylic derivatives were designed, synthesized, and screened in enzymatic and cellular inhibitory activities. All compounds showed moderate to significant potency. The SAR analyses indicated that the semicarbazone linker is better than the 1,2,3-triazole linker. Among semicarbazone compounds that R1 bearing di-chain amino groups exhibited superior activities to those with morpholino group. Furthermore, compounds with electron-withdrawing groups at the 2-position or 4-position on the terminal phenyl ring were more active. Among these, compounds 7g, 7i, 7m and 7n exhibited the inhibitory potency in the low micromolar range and displayed negligible level of cytotoxicity against normal HeLa cells. In addition, the study suggested that the aryl-acrylic is an interesting novel scaffold for IDO1 inhibition for further development.

Human cancer cells compensate the genes unfavorable for translation by N 6-methyladenosine modification and enhance their translation efficiency.

BackgroundN6-methyladenosine (m6A) is the methylation of RNA adenosines that participates in multiple biological processes, such as facilitating translation of host genes via the reader protein YTHDF1. The core writer protein of m6A in humans is METTL3.MethodsWe utilized YTHDF1 target genes and normal or si-METTL3 NGS (next-generation sequencing) data from HeLa cells generated by a previous work and collected known human oncogenes from a website. We evaluated the translation capability of these m6A genes or oncogenes by comparing their mRNA lengths and codon usage bias. Additionally, we calculated the translation efficiency of all genes expressed in the normal or si-METTL3 HeLa cells using NGS data.ResultsThe m6A genes are enriched in oncogenes compared to the non-m6A genes. We observed significantly longer mRNA lengths for the m6A genes, especially for the oncogenes. We also observed stronger codon usage bias for the m6A genes than for the non-m6A genes. We provided evidence that the longer mRNA lengths and stronger codon bias were unfavorable for translation. However, this disadvantage was compensated by m6A modification because the m6A genes but not the non-m6A genes showed higher translation efficiencies in normal cells than in si-METTL3 cells.ConclusionsHeLa cells compensate for genes unfavorable for translation by m6A modification and enhance their translation efficiency. This compensation could originally have been designed for oncogenes, since we observed enrichment of m6A genes in the oncogenes. If oncogenes modified by m6A obtain higher translation efficiencies and eventually facilitate cancer cell proliferation, then this strategy may be used by cancers for rapid cell growth.

Enzyme-/Redox-Responsive Mesoporous Silica Nanoparticles Based on Functionalized Dopamine as Nanocarriers for Cancer Therapy

Mesoporous silica nanoparticles (MSNs) have been proved potential nanocarriers for efficient stimuli-triggered drug delivery systems (DDSs) in cancer therapy. We have developed a novel pepsin enzyme-responsive MSN based on mussel mimetic coating of dopamine for controlled release of drug delivery via a facile one-pot strategy. Herein, to improve drug release efficiency for cancer therapy, a novel dual-sensitive (enzyme- and redox-) MSN based on functionalized dopamine containing both peptide and disulfide bonds was designed and prepared. In detail, cystine-dopamine (Cy-DA) was newly synthesized and used as a monomer to self-polymerize into a coating on MSNs via simple a one-pot reaction to give rise to a chemotherapy drug [e.g., doxorubicin (DOX)] delivery system poly-Cy-DA-MSN. The in vitro cellular cytotoxicity tests of normal Marc-145 cells and HeLa cells showed that poly-Cy-DA-MSN was nontoxic, highly biocompatible, and suitable as drug carriers in controlled release DDS (CDDS). Because of the peptide...

SPP1 inhibition improves the cisplatin chemo-sensitivity of cervical cancer cell lines.

Cisplatin (DDP)-based chemotherapy is a standard strategy for cervical cancer, while chemoresistance remains a huge challenge. In the present study, we aimed to explore the effects of SPP1 on the proliferation and apoptosis rate of the HeLa cervical cancer cell line with cisplatin (DDP) resistance. Microarray analysis was employed to select differentially expressed genes in cervical cancer tissues and adjacent tissues. Then, we established a DDP-resistant HeLa cell line (res-HeLa). Western blotting was used to detect SPP1 expression in both tissue and cells. After the transfection with si-SPP1 and pcDNA3.1-SPP1, colony formation and MTT assays were applied to detect cell proliferation changes. Flow cytometry was employed to detect the cell apoptosis rate. Western blotting was performed to verify the activation of PI3K/Akt signal pathway proteins related to DDP resistance. SPP1 was overexpressed in cervical cancer tissues and cell lines. Compared to normal HeLa cells, expression of SPP1 was significantly enhanced in res-HeLa cells. SPP1 knockdown resulted in repressed proliferation and enhanced apoptosis of res-HeLa cells, which could be reversed by SPP1 overexpression in HeLa cells. Additionally, downregulation of SPP1 improved the DDP sensitivity of HeLa by inhibiting the PI3K/Akt signaling pathway. SPP1 inhibition could suppress proliferation, induce apoptosis and increase the DDP chemo-sensitivity of HeLa cells.

Determination of three active components in Euphorbia humifusa willd. Using high-performance liquid chromatography with diode-array detection and autophagy and apoptosis analysis of normal rat kidney and hela cells

Background: Euphorbia humifusa Willd. (EH) is a kind of Chinese medicinal plant belonging to the family Euphorbiaceae, which is traditionally used for influenza, jaundice, hepatitis B virus, hypotension, inflammation, etc. In a modern study, active ingredients of EH reported to exhibit antioxidant, anticancer, and other properties. However, there are few reports showing that EH and its active compounds have inhibitory effects on cervical cancer through autophagy and apoptosis. Objective: To evaluate the anticervical cancer activity of EH and its main active ingredient Gallic acid (GA) by studying on autophagy and apoptosis of normal rat kidney (NRK) and HeLa cell lines, respectively. Materials and Methods: GA, kaempferol (KA), and quercetin (QU) are the main active compounds of EH. Identification and quantification of three substances from four batch samples obtained from four areas in Xinjiang were analyzed by high-performance liquid chromatography with diode-array detection. The potent effects of EH on anticervical cancer were investigated through autophagy and apoptosis in HeLa and NRK cells with varying concentrations of extracts and active compound GA treatment. The antiproliferation activity against HeLa cells was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Autophagy and apoptosis in NRK and HeLa cells were observed by laser scanning confocal microscope. Quantitative data of apoptosis were estimated by Hoechst staining and Annexin-V binding assay using flow cytometry. The expression levels of autophagy-related protein (LC3 and P62) were subjected to western blot. Moreover, the autophagic vacuoles and other ultrastructures of cells were observed under transmission electron microscopy. Results: The contents of GA, KA, and QU were measured as 2.3342–3.4688, 0.4636–1.5922, and 0.9349–3.1500 mg/g, respectively. We used different concentrations of GA and the extracts of EH to treat with the line of cells, respectively. The best concentration of GA, water, and ethanol extracts inducing autophagy was 25 μg/ml, 10 mg/ml, and 10 mg/ml, respectively. The autophagy mediated with EH induced the accumulation of autophagosome, and even resulted in apoptosis. Conclusion: From our study, these results indicated that EH and GA may induce both autophagy and apoptosis in NRK and HeLa cells. The activity we studied on autophagy and apoptosis of HeLa cells may provide a new foundation for cervical cancer therapy or other related applications. Abbreviations used: EH: Euphorbia humifusa Willd.; HPLC-DAD: High-performance liquid chromatography with diode-array detection; NRK: Normal rat kidney; GA: Gallic acid; FC: Flow cytometry; LSCM: Laser scanning confocal microscope; MTT: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide; TEM: Transmission electron microscopy; KA: Kaempferol; QU: Quercetin; LC3: The light chain 3; DMEM: Dulbecco's Modified Eagle's medium; FBS: Fetal bovine serum; DMSO: Dimethyl sulfoxide; PBS: Phosphate-buffered saline; PI: Propidium iodide; IC50: Half-maximal inhibitory concentration; BFA: Bafilomycin A1.

Effect of Ku80 on the radiosensitization of cisplatin in the cervical carcinoma cell line HeLa.

Cisplatin chemotherapy in combination with radiotherapy is the primary therapeutic strategy for the treatment of cervical cancer; however, the underlying molecular mechanism for cisplatin radiosensitization remains unknown. The aim of the present study was to investigate the effect of Ku80, a DNA double-strand break (DSB) repair protein, on cisplatin radiosensitization in cervical cancer. The pre-established Ku80 suppression cervical cancer cell line HeLa/Ku80-siRNA and the normal HeLa cell line underwent 6 MV X-ray irradiation (6 Gy) individually or in combination with 5 µg/ml cisplatin treatment. Alterations in apoptosis, the cell cycle and γH2AX expression were detected. Following irradiation individually and combined with cisplatin, compared with normal HeLa cells, HeLa/Ku80-siRNAexhibited an increased rate of apoptosis (P<0.05). It was identified that the earlier cisplatin was administered following irradiation, the higher the rate of apoptosis. Cell cycle analysis indicated that, following irradiation combined with cisplatin, the cells were arrested in G1 and S phase rather than in G2/M phase following irradiation alone. Microscopic imaging of immunofluorescence staining and western blotting identified that HeLa/Ku80-siRNA cells exhibited more γH2AX foci remaining following treatment with irradiation and cisplatin, particularly in the group treated with 6 Gy irradiation for 1 h together with 23 h of exposure to cisplatin. Irradiation in combination with cisplatin promoted the apoptosis of HeLa cells in association with the inhibition of Ku80, and it was identified that the earlier cisplatin was administered following irradiation, the more apoptosis was induced. This maybe because irradiation combined with cisplatin is able to arrest cells in G1 and S phase to rapidly repair damaged DNA, and the lack of Ku80 induces the inability to repair DSB, resulting in increased apoptosis. The results of the present study suggest that Ku80 may be a potent molecular target in cisplatin radiosensitization.

Chitosan–silver nanocomposites: New functional biomaterial for health-care applications

ABSTRACTChitosan–silver nanocomposites (CS-HDA-AgNCs) was prepared using chitosan, biogenic silver nanocomposites, and crosslinker, hexamethylene 1,6-di(amino carboxysulfonate) (HDA). The film is flexible and transparent. Its physical, mechanical, thermal, hydrophilicity, and swelling properties were improved by HDA (2.5%). The antimicrobial activity of CS-HDA-AgNCs were not displayed any remarkable zone of inhibition but showed toxic effect in the presence of normal 3T3 fibroblasts and cancer HeLa cells. It decreases to ca. 5–7% for both cell lines. In conclusion, it can be mentioned that the CS-HDA-AgNCs, a kind of new functional biomaterial, could be useful for health-care applications.

Enhance chemotherapy efficacy and minimize anticancer drug side effects by using reversibly pH- and redox-responsive cross-linked unimolecular micelles

Chemotherapy side effects elimination while keeping the original therapeutic advantages has been of extensive interest over last decades. We herein develope a new pH and redox-sensitive nanogel for glutathione-mediated intracellular drug delivery employing disulfide crosselinked unimolecular micelles. We developed H40-polycaprolactone-b-polyacrylic acid-b′-methoxy poly(ethylene glycol)/poly(ethylene glycol)-folate (i.e., H40-PCL-(b-PAA-b′-MPEG/PEG-FA)2) unimolecular micelles with targeting moieties on the periphery. It was then crosslinked with cystamine in order to generate a pH and redox-sensitive nanogel. Dynamic light scattering (DLS) was performed to study pH-dependent nanogel sizes. We applied Paclitaxel, a hydrophobic anticancer drug, into delivery system and examined triggered release behaviors at different pHs upon DTT buffer exposure. Our results demonstrated that DTT presence as reductive agent within acidic environment is essential for drug release. This may potentially reduce unwanted drug release at non-cancerous acidic tissues leading to eliminated side effects. We examined biocompatibility and cytotoxicity of free nanogel and PTX-loaded nanogel to normal and cancer HeLa cells using MTT assay. Nanogel HeLa cell uptake was confirmed by Fluorescein loading into the gel followed by fluorescent microscope imaging. Our novel strategy would have profound implications in both enhanced chemotherapy efficacy and minimized side effects.

Differential Bio-Potential of ZnS Nanoparticles to Normal MDCK Cells and Cervical Carcinoma HeLa Cells

Differential Bio-Potential of ZnS Nanoparticles to Normal MDCK Cells and Cervical Carcinoma HeLa Cells